Which NAT type maps many private addresses to a single public IP using different ports?

Which NAT type maps many private addresses to a single public IP using different ports?

• A. Static NAT maps one private IP to one public IP
• B. Dynamic NAT uses a pool of public IPs
• C. PAT maps many private addresses to a single public IP using different ports
• D. NAT traversal uses tunneling to pass through NAT

Answer: (C)

This question tests how NAT can multiplex many devices behind one public IP by using ports. Port Address Translation assigns a unique source port to each internal device’s connection, while all traffic appears to come from the same public IP. The NAT device maintains a table that maps each internal IP address and port to a specific external IP address and port. When responses return, the NAT uses the port to route them back to the correct internal host. This is why many private hosts can share a single public IP. Static NAT would map one private IP to one public IP, and dynamic NAT uses a pool of public IPs but doesn’t multiplex via ports. NAT traversal is about getting through NAT for certain applications, not about address-to-port multiplexing.

This question tests how NAT can multiplex many devices behind one public IP by using ports. Port Address Translation assigns a unique source port to each internal device’s connection, while all traffic appears to come from the same public IP. The NAT device maintains a table that maps each internal IP address and port to a specific external IP address and port. When responses return, the NAT uses the port to route them back to the correct internal host. This is why many private hosts can share a single public IP. Static NAT would map one private IP to one public IP, and dynamic NAT uses a pool of public IPs but doesn’t multiplex via ports. NAT traversal is about getting through NAT for certain applications, not about address-to-port multiplexing.